server: Do not crash the server if an empty request over gRPC

goroutine 11 [running]:
github.com/osrg/gobgp/pkg/server.newNeighborFromAPIStruct(0x0, 0xb5dd20, 0xc0000b3aa0, 0xc0002d4048)
	/home/donatas/projects/gobgp/pkg/server/grpc_server.go:643 +0x57
github.com/osrg/gobgp/pkg/server.(*BgpServer).AddPeer.func1(0x4a38c9, 0xb40bc0)
	/home/donatas/projects/gobgp/pkg/server/server.go:2940 +0x36
github.com/osrg/gobgp/pkg/server.(*BgpServer).handleMGMTOp(0xc0000f3680, 0xc0004e4348)
	/home/donatas/projects/gobgp/pkg/server/server.go:240 +0x47
github.com/osrg/gobgp/pkg/server.(*BgpServer).Serve(0xc0000f3680)
	/home/donatas/projects/gobgp/pkg/server/server.go:422 +0x735
created by main.main
	/home/donatas/projects/gobgp/cmd/gobgpd/main.go:153 +0x3cf

To replicate:

from __future__ import absolute_import
from __future__ import print_function

import grpc
from google.protobuf.any_pb2 import Any

import gobgp_pb2
import gobgp_pb2_grpc
import attribute_pb2

_TIMEOUT_SECONDS = 1000

def run():
    channel = grpc.insecure_channel('localhost:50051')
    stub = gobgp_pb2_grpc.GobgpApiStub(channel)

    peers = stub.AddPeer(
        gobgp_pb2.AddPeerRequest(
        ),
        _TIMEOUT_SECONDS,
    )

    for peer in peers:
        print(peer)

if __name__ == '__main__':
    run()

Signed-off-by: Donatas Abraitis <donatas.abraitis@gmail.com>

0 files changed, 0 insertions, 0 deletions